Feature

YFMRT/YFMRT(R) vane axial fans for metro and tunnel are researched and designed independently by digesting and absorbing the technology of congener foreign advanced fans and making a lot of investigations and surveys in metro and tunnel engineering systems. Air performance and structure design of the series of fans can reach international advanced level, with features of high pressure, high efficiency, high reliability, low sound and anti surge. Meanwhile, they may be used as fire smoke exhaust in an emergency.

Max impeller diameter of these series of fan is 2800mm, with max volume of 980000m³/h and max pressure of 2300Pa. YFMRT is unidirectional vane axial fan for metro and tunnel, and YFMRT(R) is bidirectional vane axial fan for metro and tunnel.

Advanced Design

-- Advanced FEA technology is used for optimized structure design and fans finally perform auxiliary test experiment for conformation. Heat inflation of material and the strength at high temperature are fully considered when designing to ensure a high reliability of running for emergency high temperature smoke exhaust.

-- Impeller hub and blades are pressure casted in quality high strength aluminium alloy and every blade must be qualification tested by X ray detection.

-- I Using high strength bolts fastening blades with hub to ensure long-term reliable working.

-- Fan casing is formed by wholly welding using high quality thick steel plate to ensure high strength structure.

High Efficiency and Low Noise

-- Advanced CFD technology is used for optimized design of air performance to give a good air flow quality with high efficiency and low sound.

-- Blades are designed with optimal airfoil profile which has high air efficiency and low sound. Adjusting blade pitch in the static state and choosing.

-- According to requirements of metro tunnel, it may choose enclosed and damp heat motor anti high temperature, and fans are designed to work.

-- continually at least 60min under 250℃ without mechanical ,electrical and structural faults, and are used for fire smoke exhaust in an emergency.

Anti Surge Patent Design

When trains passing through tunnel like piston, the air pressure in the tunnel may change and the fan will work against high pressure. In order to prevent fan working at stall point and happening to surge, anti surge equipment is designed matching with fan. The anti surge equipment gets the patent and has a good performance to ensure fan work without surging.

Bidirectional and Reversible design

-- YFMRT(R) series of fan are bidirectional and reversible, composed of totally symmetrical airfoil blades to ensure almost the same performance for bidirection.

-- Special aluminum alloy impeller with small moment of inertia has a short starting and stopping time. With optional normal-reverse switch component when soft start, fans can finish normal-reverse transfer in 45 seconds to ensure emergency quick transfer.

Strong Corrosion Resistance

Fans are provided with damp-heat proof type motor. All static components of fans shall be treated with high strength corrosion resistance, surface treatment using paint or surface zinc plating to ensure long-term anticorrosion.

Convenient Installation and Maintenance

-- The standard installation method is horizontal, and also vertical for convenient mounting.

Technical

Fans shall be cylindrical vane axial fan directly driven by the motor. Blades shall be completely symmetrical airfoil design and static guide vanes shall be set in the fan cylinder. Fans shall work as normal-reverse ventilation by changing rotate direction of the motor, with almost the same performance.

Fan Casing

Fan casing should be constructed of continuously welded high quality steel plate, which shall be rolled to cylinder firstly and then wholly welded. Fan casing and motor support should be welded firmly as a whole to ensure enough strength and stiffness to bear dynamic load, meanwhile it should ensure manufacture precision of fan casing to make sure that the motor axis is identical with casing centerline.

Wheel

Rotor blade should be optimized airfoil design, with asymmetrical airfoil for unidirectional fans and completely symmetrical airfoil for bidirectional fans to ensure almost the same performance between normal and reverse rotation.
Hub and blades should be casted in high strength aluminum alloy. Each blade must be tested by X ray to ensure a high quality for reliable running.
Blades should be fastened to hub with high strength bolts. Every impeller should be dynamically balanced.
Blade pitch should be adjustable in static state to meet different operating conditions.

Fairing

Fairing should be streamlined design, made by pressure extruding by steel mould using high strength aluminum alloy. Fairing should be fastened to impeller by bolts and may be dismounted conveniently.
Anti surge device (only for impeller diameter over 1250 mm)
In order to prevent stall surge, fans should be set with mechanical anti surge device to ensure working without surge.

Motor

Motor should be squirrel cage asynchronous motor cooled by natural ventilation, standard product of totally enclosed type of damp heat, class H insulation, IP55. Motors are lubricated using grease by extended lubricating nipple on fan shell. Motor lead cables should extend to the junction box on the fan shell for easy wiring.

Surface treatment

Surface of the fan should be treated with anticorrosion and antirust. It should be treated with paint （options：surface zinc plating or what specified by users）and the surface should be clean and smooth, without bubble, crinkle and spall faults to ensure long term anticorrosion.

Smoke Removal Certification

Fans must pass testing according to GA211-2009《High Temperature Test Method for Fire Smoke Extraction Fan》by inspection agencies designated by China Certification Center for Fire Products Ministry of Public Security. Fans shall continually run for at least 60min at 250℃ reliably and have relevant certificate.

Nameplate

Aluminum nameplate shall be permanently fixed and clearly indicate legible fan number, model and product serial number (i.e. unique identification of each fan), ensuring that customers can conveniently query the history records of the accessories.